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Diffstat (limited to 'tkhtml1/src/htmlindex.c')
| -rw-r--r-- | tkhtml1/src/htmlindex.c | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/tkhtml1/src/htmlindex.c b/tkhtml1/src/htmlindex.c new file mode 100644 index 0000000..7b488a1 --- /dev/null +++ b/tkhtml1/src/htmlindex.c @@ -0,0 +1,505 @@ +/* +** Routines that deal with indexes +** +** Copyright (C) 1997-2000 D. Richard Hipp +** +** This library is free software; you can redistribute it and/or +** modify it under the terms of the GNU Library General Public +** License as published by the Free Software Foundation; either +** version 2 of the License, or (at your option) any later version. +** +** This library is distributed in the hope that it will be useful, +** but WITHOUT ANY WARRANTY; without even the implied warranty of +** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +** Library General Public License for more details. +** +** You should have received a copy of the GNU Library General Public +** License along with this library; if not, write to the +** Free Software Foundation, Inc., 59 Temple Place - Suite 330, +** Boston, MA 02111-1307, USA. +** +** Author contact information: +** drh@acm.org +** http://www.hwaci.com/drh/ +*/ +#include <ctype.h> +#include <tk.h> +#include <string.h> +#include "htmlindex.h" + +/* +** Return a pointer to the Nth HtmlElement in the list. If there +** is no Nth element, return 0 if flag==0 and return either the first +** or last element (whichever is closest) if flag!=0 +*/ +HtmlElement *HtmlTokenByIndex(HtmlWidget *htmlPtr, int N, int flag){ + HtmlElement *p; + int n; + + if( N > htmlPtr->nToken/2 ){ + /* Start at the end and work back toward the beginning */ + for(p=htmlPtr->pLast, n=htmlPtr->nToken; p; p=p->base.pPrev){ + if( p->base.type!=Html_Block ){ + if( n==N ){ TestPoint(0); break; } + n--; + TestPoint(0); + }else{ + TestPoint(0); + } + } + }else{ + /* Start at the beginning and work forward */ + for(p=htmlPtr->pFirst; p; p = p->base.pNext){ + if( p->base.type!=Html_Block ){ + N--; + if( N<=0 ){ TestPoint(0); break; } + }else{ + TestPoint(0); + } + } + } + return p; +} + +/* +** Return the token number for the given HtmlElement +*/ +int HtmlTokenNumber(HtmlElement *p){ + int n = 0; + + while( p ){ + if( p->base.type!=Html_Block ){ + TestPoint(0); + n++; + }else{ + TestPoint(0); + } + p = p->base.pPrev; + } + return n; +} + +/* +** Find the maximum index for the given token +*/ +static void maxIndex(HtmlElement *p, int *pIndex){ + if( p==0 ){ + *pIndex = 0; + TestPoint(0); + }else{ + switch( p->base.type ){ + case Html_Text: + *pIndex = p->base.count-1; + TestPoint(0); + break; + case Html_Space: + if( p->base.style.flags & STY_Preformatted ){ + *pIndex = p->base.count-1; + TestPoint(0); + }else{ + *pIndex = 0; + TestPoint(0); + } + break; + default: + *pIndex = 0; + TestPoint(0); + break; + } + } +} + +/* +** Given a Block and an x coordinate, find the Index of the character +** that is closest to the given x coordinate. +** +** The x-coordinate might specify a point to the left of the block, +** in which case the procedure returns the first token and a character +** index of 0. Or the x-coordinate might specify a point to the right +** of the block, in which case the last token is returned with an index +** equal to its last character. +*/ +static void FindIndexInBlock( + HtmlWidget *htmlPtr, /* The widget */ + HtmlBlock *pBlock, /* The block */ + int x, /* The x coordinate */ + HtmlElement **ppToken, /* Write the closest token here */ + int *pIndex /* Write the charater index in ppToken here */ +){ + HtmlElement *p; + Tk_Font font; + int len; + int n; + + p = pBlock->base.pNext; + HtmlLock(htmlPtr); + font = HtmlGetFont(htmlPtr, p->base.style.font); + if( HtmlUnlock(htmlPtr) ){ + *ppToken = p; + *pIndex = 0; + return; + } + if( x <= pBlock->left ){ + *ppToken = p; + *pIndex = 0; + TestPoint(0); + return; + }else if( x>= pBlock->right ){ + *ppToken = p; + *pIndex = 0; + while( p && p->base.type!=Html_Block ){ + *ppToken = p; + p = p->base.pNext; + TestPoint(0); + } + p = *ppToken; + if( p && p->base.type==Html_Text ){ + *pIndex = p->base.count - 1; + TestPoint(0); + }else{ + TestPoint(0); + } + return; + } + if( pBlock->n==0 ){ + *ppToken = p; + *pIndex = 0; + TestPoint(0); + }else{ + TestPoint(0); + } + n = Tk_MeasureChars(font, pBlock->z, pBlock->n, x - pBlock->left, 0, &len); + *pIndex = 0; + *ppToken = 0; + while( p && n>=0 ){ + switch( p->base.type ){ + case Html_Text: + if( n<p->base.count ){ + *pIndex = n; + TestPoint(0); + }else{ + *pIndex = p->base.count - 1; + TestPoint(0); + } + *ppToken = p; + n -= p->base.count; + break; + case Html_Space: + if( p->base.style.flags & STY_Preformatted ){ + if( n<p->base.count ){ + *pIndex = n; + TestPoint(0); + }else{ + *pIndex = p->base.count - 1; + TestPoint(0); + } + *ppToken = p; + n -= p->base.count; + }else{ + *pIndex = 0; + *ppToken = p; + n--; + TestPoint(0); + } + break; + default: + TestPoint(0); + break; + } + if( p ){ + p = p->base.pNext; + TestPoint(0); + }else{ + TestPoint(0); + } + } +} + +/* +** Convert an Element-based index into a Block-based index. +** +** In other words, given a pointer to an element and an index +** of a particular character within that element, compute a +** pointer to the HtmlBlock used to display that character and +** the index in the HtmlBlock of the character. +*/ +void HtmlIndexToBlockIndex( + HtmlWidget *htmlPtr, /* The widget */ + HtmlIndex sIndex, /* The index to be translated */ + HtmlBlock **ppBlock, /* Write the corresponding block here */ + int *piIndex /* Write the block index here */ +){ + int n = sIndex.i; + HtmlElement *p; + + if( sIndex.p==0 ){ + *ppBlock = 0; + *piIndex = 0; + TestPoint(0); + return; + } + p = sIndex.p->base.pPrev; + while( p && p->base.type!=Html_Block ){ + switch( p->base.type ){ + case Html_Text: + n += p->base.count; + TestPoint(0); + break; + case Html_Space: + if( p->base.style.flags & STY_Preformatted ){ + n += p->base.count; + TestPoint(0); + }else{ + n++; + TestPoint(0); + } + break; + default: + TestPoint(0); + break; + } + p = p->base.pPrev; + } + if( p ){ + *ppBlock = &p->block; + *piIndex = n; + TestPoint(0); + return; + } + for(p=sIndex.p; p && p->base.type!=Html_Block; p=p->base.pNext){ + TestPoint(0); + } + *ppBlock = &p->block; + *piIndex = 0; +} + + + +/* +** Given a base index name (without any modifiers) return a pointer +** to the token described, and the character within that token. +** +** Valid input forms include: +** +** N.M Token number N (with numbering starting at 1) and +** character number M (with numbering starting at 0). +** +** end The end of all text +** +** N.last Last character of token number N. +** +** sel.first First character of the selection. +** +** sel.last Last character of the selection. +** +** ins The character holding the insertion cursor. +** +** @X,Y The character a location X,Y of the clipping window. +** +** Zero is returned if we are successful and non-zero if there is +** any kind of error. +** +** If the given token doesn't exist (for example if there are only 10 +** tokens and 11.5 is requested) then *ppToken is left pointing to NULL. +** But the function still returns 0 for success. +*/ +static int DecodeBaseIndex( + HtmlWidget *htmlPtr, /* The HTML widget we are dealing with */ + const char *zBase, /* The base index string */ + HtmlElement **ppToken, /* Write the pointer to the token here */ + int *pIndex /* Write the character offset here */ +){ + int x, y; + int n; + int i; + HtmlElement *p; + HtmlBlock *pBlock; + HtmlBlock *pNearby; + int dist = 1000000; + int rc = 0; + + while( isspace(*zBase) ){ TestPoint(0); zBase++; } + switch( *zBase ){ + case '1': case '2': case '3': case '4': case '5': + case '6': case '7': case '8': case '9': + n = sscanf(zBase,"%d.%d",&x,&y); + if( n>0 ){ + p = *ppToken = HtmlTokenByIndex(htmlPtr, x, 0); + TestPoint(0); + }else{ + TestPoint(0); + } + if( n==2 ){ + *pIndex = y; + TestPoint(0); + }else{ + for(i=1; isdigit(zBase[i]); i++){ TestPoint(0); } + if( zBase[i]==0 ){ + *pIndex = 0; + TestPoint(0); + }else if( strcmp(&zBase[i],".last")==0 ){ + maxIndex(p,pIndex); + TestPoint(0); + }else{ + rc = 1; + TestPoint(0); + } + } + break; + case 'e': + if( strcmp(zBase,"end")==0 ){ + p = *ppToken = htmlPtr->pLast; + maxIndex(p,pIndex); + TestPoint(0); + }else{ + rc = 1; + TestPoint(0); + } + break; + case 's': + if( strcmp(zBase,"sel.first")==0 ){ + *ppToken = htmlPtr->selBegin.p; + *pIndex = htmlPtr->selBegin.i; + TestPoint(0); + }else if( strcmp(zBase,"sel.last")==0 ){ + *ppToken = htmlPtr->selEnd.p; + *pIndex = htmlPtr->selEnd.i; + TestPoint(0); + }else{ + rc = 1; + TestPoint(0); + } + break; + case 'i': + if( strcmp(zBase,"insert")==0 ){ + *ppToken = htmlPtr->ins.p; + *pIndex = htmlPtr->ins.i; + TestPoint(0); + }else{ + rc = 1; + TestPoint(0); + } + break; + case '@': + n = sscanf(zBase,"@%d,%d",&x,&y); + if( n!=2 ){ + rc = 1; + TestPoint(0); + break; + } + x += htmlPtr->xOffset; + y += htmlPtr->yOffset; + pNearby = 0; + *ppToken = htmlPtr->pLast; + *pIndex = 0; + for(pBlock=htmlPtr->firstBlock; pBlock; pBlock=pBlock->pNext){ + int dotest; + if( pBlock->n==0 ){ + switch( pBlock->base.pNext->base.type ){ + case Html_LI: + case Html_IMG: + case Html_INPUT: + case Html_TEXTAREA: + case Html_SELECT: + dotest = 1; + TestPoint(0); + break; + default: + dotest = 0; + TestPoint(0); + break; + } + }else{ + dotest = 1; + TestPoint(0); + } + if (dotest){ + if( pBlock->top <= y && pBlock->bottom >= y ){ + if( pBlock->left > x ){ + if( pBlock->left - x < dist ){ + dist = pBlock->left - x; + pNearby = pBlock; + TestPoint(0); + }else{ + TestPoint(0); + } + }else if( pBlock->right < x ){ + if( x - pBlock->right < dist ){ + dist = x - pBlock->right; + pNearby = pBlock; + TestPoint(0); + }else{ + TestPoint(0); + } + }else{ + HtmlLock(htmlPtr); + FindIndexInBlock(htmlPtr, pBlock, x, ppToken, pIndex); + if( HtmlUnlock(htmlPtr) ) return 1; + TestPoint(0); + break; + } + }else{ + int distY; + int distX; + + if( pBlock->bottom < y ){ + distY = y - pBlock->bottom; + TestPoint(0); + }else{ + distY = pBlock->top - y; + TestPoint(0); + } + if( pBlock->left > x ){ + distX = pBlock->left - x; + TestPoint(0); + }else if( pBlock->right < x ){ + distX = x - pBlock->right; + TestPoint(0); + }else{ + distX = 0; + TestPoint(0); + } + if( distX + 4*distY < dist ){ + dist = distX + 4*distY; + pNearby = pBlock; + TestPoint(0); + }else{ + TestPoint(0); + } + } + } + } + if( pBlock==0 ){ + if( pNearby ){ + HtmlLock(htmlPtr); + FindIndexInBlock(htmlPtr, pNearby, x, ppToken, pIndex); + if( HtmlUnlock(htmlPtr) ) return 1; + TestPoint(0); + }else{ + TestPoint(0); + } + }else{ + TestPoint(0); + } + break; + default: + rc = 1; + TestPoint(0); + break; + } + return rc; +} + +/* +** This routine decodes a complete index specification. A complete +** index consists of the base specification followed by modifiers. +*/ +int HtmlGetIndex( + HtmlWidget *htmlPtr, /* The widget */ + const char *zIndex, /* Complete text of the index spec */ + HtmlElement **ppToken, /* Write the pointer to the token here */ + int *pIndex /* Write the character offset here */ +){ + TestPoint(0); + return DecodeBaseIndex(htmlPtr, zIndex, ppToken, pIndex); +} |